## Algebra 2 (1st Edition)

We find: $$(x+y)^2 = x^2 + y^2 \\ x^2 +2xy + y^2 = x^2 + y^2 \\ 2xy = 0$$ Thus, we observe that the two expressions are only equal when x or y are equal to zero. However, the expressions are not equivalent as the expressions are not always the same.